According to Article 3.5 of the directive 2013/59/EURATOM, radiation protection “shall be optimised with the aim of keeping the magnitude of individual doses […] as low as reasonably achievable […]”.
In addition to the customization of protocols for CT studies, a dose efficiency index (DEI) for the device itself could help to objectively compare CT systems under standardized measurement and evaluation conditions.
We designed a method to calculate a dose-efficiency index based on the results of a project funded by the German Ministry of the...
Description of activity and work performed
The individual steps for the calculation of the dose-efficiency-index (DEI) are shown in Fig. 1. A minimum of 200 images of the inserts and a similar amount of images without inserts has to be acquired for each set of exposure parameters. For each insert, the value of the corresponding area under the ROC curve (AUC), using the Hotelling observer with Laguerre-Gauss channels, is obtained. Repetition of this approach for 5 different devices of the same type provided a standard deviation of 2.2 % for the...
Conclusion and recommendations
The determination of a DEI for the detection of low-contrast structures in CT will enable transparent and unbiased comparisons of the hardware and software of CT systems. Preliminary studies have shown that this is possible with a feasible effort.
H. de las Heras Gala; Oberschleißheim/DE - nothing to disclose G. Brix; Oberschleißheim/DE - nothing to disclose A. Giussani; Oberschleißheim/DE - nothing to disclose
 Racine, Damien; Viry, Anaïs; Edyvean, Sue; Verdun, Francis R. Characterization of clinical CT systems using a dose efficiency index (DEI) - Project 3613S20007. Ressortforschungsberichte zum Strahlenschutz; 128/17. Bundesamt für Strahlenschutz (September 2017).
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